Introduction: Hippocampal differentiation

  • The hippocampus shows a long axis anterior-posterior differentiation of function
  • Poppenk et al. (2013) suggested that the type of processing in the hippocampus varied from fine to coarse grained in a posterior to anterior direction, based on evidence that receptive fields vary from narrow at the posterior end of the hippocampus to broad at the anterior end (Kjelstrup et al., 2008; Maurer Vanrhoads, Sutherland, Lipa, & McNaughton, 2005).
  • Anterior = pattern completion, posterior = pattern separation

Grady et al., 2020

- The anterior and posterior portions may undergo different developmental trajectories across the lifespan, and may give rise to some of the cognitive changes that commonly accompany the aging process (i.e., episodic memory)

Langnes et al., 2020

## Sleep and the hippocampus

  • Hippocampus involved in sleep architecture (theta in REM, sharp wave ripples in NREM, coupling with slow wave)
  • Chronic sleep disruption and circadian rhythmicity affect hippocampal neurogenesis in animals (Raven et al., 2018; Kreutzmann et al., 2015)
  • In older adults, more robust rest-activity rhythms were associated with greater anterior hippocampal volume (Sherman et al., 2015)
  • Sleep disturbance in older adults predicts increasingly worse scores on standardized neuropsychological tests, including memory subcomponents that depend upon the hippocampus (HVLT)

Research Question

Are sleep-wake patterns associated with volumetric differences along the hippocampal long axis that underlie episodic memory?

Methods

  • Healthy younger (n = 43, age = 21.5, ±3.86) and older (n = 43, age = 68.2, ±5.63) adults
  • Actigraphy
  • fMRI scanning
  • Episodic memory measures: associative memory task, CVLT (older adults only)
  • Working memory/novelty measure: repeat task

Actigraphy

  • Selected mean sleep duration, acrophase, amplitude, and interdaily stability as measures of interest

- Planned to use CVLT, but did not have data available from younger adults :(

CVLT

Associative memory task

  • Had associative memory task data, but really only have a good measure of intial encoding and short-term recall (no long-term recall measure)
  • This is problematic because really wanted long-term recall measure (Langnes et al. 2020)

Repeat task

  • 1-back working memory task
  • Novelty vs. familiarity

Participants

Young Adults Older Adults
n 43 55
Group = Older Adults (%) 0 ( 0.0) 55 (100.0)
age (mean (SD)) 21.51 (3.86) 68.20 (5.63)
sex = Male (%) 17 (39.5) 12 ( 21.8)
years_educ (mean (SD)) 14.62 (2.38) 16.88 (2.94)
global_psqi (mean (SD)) 4.21 (1.79) 4.40 (2.15)
cesd_score (mean (SD)) 7.00 (4.08) 2.00 (NA)
gds_total (mean (SD)) 0.00 (0.00) 1.20 (2.30)
sleep_time_mean_sleep (mean (SD)) 398.57 (97.86) 404.55 (85.83)
efficiency_mean_sleep (mean (SD)) 81.43 (6.92) 80.62 (9.04)
total_ac_mean_active (mean (SD)) 326940.99 (189192.81) 251197.38 (89924.99)
actamp (mean (SD)) 1.61 (0.29) 1.58 (0.34)
IS (mean (SD)) 0.42 (0.11) 0.54 (0.12)
actphi (mean (SD)) 16.38 (1.45) 14.73 (1.65)

Parcellation

  • Used brainlife.io to obtain hippocampal volume measures
  • Uploaded BIDS dataset

brainlife.io - Checked orientation of all T1 images - Ran ACPC alignment

Originial T1:

T1

ACPC aligned:

ACPC alignment

  • Used “HBT” divisions (Iglesias et al., 2015)
  • This parcellation was based on both ex vivo and in vivo data

Manual labelling

In vivo segmentation

Hippocampal parcellation

Results

Aging and hippocampal volume

ICV normalized

We wanted to look at hippocampal volume independently of total intracranial volume, so we calculated HC volume as follows: adjusted HC volume = raw HC volume – b X (ICV – average ICV), where b is the slope of regression of the raw HC volume on ICV (Brehmer et al., 2020).







## Memory Performance




|                                         |Young Adults     |Older Adults      |
|:----------------------------------------|:----------------|:-----------------|
|n                                        |43               |52                |
|Group = Older Adults (%)                 |0 (0.0)          |52 (100.0)        |
|cvlt_sdelay_recall_zscore (mean (SD))    |NaN (NA)         |0.64 (1.03)       |
|cvlt_ldelay_recall_zscore (mean (SD))    |NaN (NA)         |0.54 (0.95)       |
|cvlt_recognition_hits_zscore (mean (SD)) |NaN (NA)         |-0.14 (1.00)      |
|cvlt_recognition_fp_zscore (mean (SD))   |NaN (NA)         |-0.17 (0.96)      |
|cvlt_zscore (mean (SD))                  |NaN (NA)         |0.27 (0.73)       |
|acc_mean.learning (mean (SD))            |0.88 (0.16)      |0.80 (0.17)       |
|acc_std.learning (mean (SD))             |0.24 (0.16)      |0.34 (0.14)       |
|rt_c_mean.learning (mean (SD))           |1732.99 (401.86) |2770.81 (1688.63) |
|rt_c_std.learning (mean (SD))            |739.88 (288.11)  |1388.35 (1623.11) |
|acc_mean.test (mean (SD))                |0.90 (0.11)      |0.84 (0.10)       |
|acc_std.test (mean (SD))                 |0.24 (0.16)      |0.33 (0.13)       |
|rt_c_mean.test (mean (SD))               |2459.76 (211.57) |2773.37 (225.69)  |
|rt_c_std.test (mean (SD))                |342.31 (141.26)  |450.80 (107.35)   |

record_id acc_mean.learning acc_mean.test

1 40550 0.25 0.6666667


## Hippocampal volume and CVLT performance within older adults
- Only had CVLT data for older adults
- Did not see relationship between hippocampal volume and CVLT memory


<img src="hippocampus_files/figure-html/unnamed-chunk-7-1.png" style="display: block; margin: auto;" />

## Sleep and CVLT performance

<img src="hippocampus_files/figure-html/unnamed-chunk-8-1.png" style="display: block; margin: auto;" />

## Hippocampal volume and associative memory task performance

- Using the associative memory task allowed us to include the young adult comparison group.
- There was a significant Group by hippocampal head volume effect on associative memory accuracy during the test phase, where older adults showed a positive association between hippocampal head volume and memory accuracy, whereas young adults showed the opposite trend.

<img src="hippocampus_files/figure-html/unnamed-chunk-9-1.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-9-2.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-9-3.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-9-4.png" style="display: block; margin: auto;" />

## Sleep and memory performance
- In this study, young and older adult age groups showed differential relationships between acrophase and (1) accuracy during the test phase, and (2) response time on correct trials during both the learning and test phases

<img src="hippocampus_files/figure-html/unnamed-chunk-10-1.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-10-2.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-10-3.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-10-4.png" style="display: block; margin: auto;" />

<img src="hippocampus_files/figure-html/unnamed-chunk-11-1.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-11-2.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-11-3.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-11-4.png" style="display: block; margin: auto;" />

## Hippocampal volume and sleep 

- Nada!

<img src="hippocampus_files/figure-html/unnamed-chunk-12-1.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-12-2.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-12-3.png" style="display: block; margin: auto;" />

## Discussion
- Did not identify evidence of a long-axis encoding/retrieval differentiation using either of our episodic memory tasks
- Among older adults, greater hippocampal head volume was associated with greater associative memory accuracy during test. 
- Acrophase was also associated with greater associative memory accuracy during test, consistent with ([Ming Yi Lee et al., 2021](https://doi.org/10.1016/j.nbscr.2021.100065)) which recently found that older adults with delayed acrophase were less likely to have better cognition
- But, acrophase was not associated with hippocampal head volume
- No other selected sleep measures (mean sleep duration, rhythm amplitude, interdaily stability, acrophase) were  associated with hippocampal volume at conventional statistical thresholds.
- Did not see any relationship with CVLT performance in contrast to prior literature.

## Limitations
- Lack of CVLT-II data for young adult group prevented examination of different components of memory across adult development
- Hoped to partially overcome this limitation by evaluating relationships between hippocampal volume and aspects of performance on an associative memory task. This task provided behavioral measures much narrower in scope compared to the CVLT-II, with instead only measures of initial encoding and short-term recall. 
- Participants across both age groups performed well on this task, making it difficult to tease out functional variability.
- Healthy group not representative of "normal" aging
- Cross-sectional nature of the study may have prevented us from picking up on the key features of sleep that are important markers of cognitive health. Maybe the trajectories of these sleep patterns rather than their raw values are more revealing about the expected status of an individual’s cognitive performance and underlying brain health.



# All analyses below
## Hippocampal volume and associative memory 
- Excluded participants below chance accuracy

<img src="hippocampus_files/figure-html/unnamed-chunk-13-1.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-13-2.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-13-3.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-13-4.png" style="display: block; margin: auto;" />

## Sleep 

<img src="hippocampus_files/figure-html/unnamed-chunk-14-1.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-14-2.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-14-3.png" style="display: block; margin: auto;" />

## Sleep and hippocampal volume

<img src="hippocampus_files/figure-html/unnamed-chunk-15-1.png" style="display: block; margin: auto;" />


## Sleep and cognition

<img src="hippocampus_files/figure-html/unnamed-chunk-16-1.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-16-2.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-16-3.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-16-4.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-16-5.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-16-6.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-16-7.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-16-8.png" style="display: block; margin: auto;" /><img src="hippocampus_files/figure-html/unnamed-chunk-16-9.png" style="display: block; margin: auto;" />



## Stats

Call:

lm(formula = acc_mean.learning ~ Hippocampal_head * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.51771 -0.03858 0.03792 0.08202 0.17520

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1.204e+00 2.704e-01 4.452 2.73e-05 ***

Hippocampal_head -8.901e-05 7.792e-05 -1.142 0.257

GroupOlder Adults -5.322e-01 3.668e-01 -1.451 0.151

Hippocampal_head:GroupOlder Adults 1.408e-04 1.099e-04 1.281 0.204

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.1396 on 80 degrees of freedom

Multiple R-squared: 0.06475, Adjusted R-squared: 0.02968

F-statistic: 1.846 on 3 and 80 DF, p-value: 0.1454

Call:

lm(formula = acc_mean.learning ~ Hippocampal_head + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.55334 -0.03241 0.03999 0.08152 0.16358

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 9.588e-01 1.920e-01 4.994 3.34e-06 ***

Hippocampal_head -1.820e-05 5.514e-05 -0.330 0.7423

GroupOlder Adults -6.425e-02 3.403e-02 -1.888 0.0626 .

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.1401 on 81 degrees of freedom

Multiple R-squared: 0.04556, Adjusted R-squared: 0.022

F-statistic: 1.933 on 2 and 81 DF, p-value: 0.1513

Call:

lm(formula = rt_c_mean.learning ~ Hippocampal_head * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-1451.0 -426.1 -103.2 334.6 3802.2

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1370.1497 1428.7625 0.959 0.340

Hippocampal_head 0.1008 0.4117 0.245 0.807

GroupOlder Adults 424.4801 1938.0878 0.219 0.827

Hippocampal_head:GroupOlder Adults 0.1022 0.5805 0.176 0.861

Residual standard error: 737.5 on 80 degrees of freedom

Multiple R-squared: 0.2037, Adjusted R-squared: 0.1738

F-statistic: 6.82 on 3 and 80 DF, p-value: 0.0003762

Call:

lm(formula = rt_c_mean.learning ~ Hippocampal_head + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-1461.8 -429.9 -100.4 346.9 3818.0

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1192.2553 1004.4516 1.187 0.239

Hippocampal_head 0.1522 0.2885 0.528 0.599

GroupOlder Adults 764.3598 178.0484 4.293 4.85e-05 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 733.1 on 81 degrees of freedom

Multiple R-squared: 0.2033, Adjusted R-squared: 0.1837

F-statistic: 10.34 on 2 and 81 DF, p-value: 0.0001003

Call:

lm(formula = acc_mean.learning ~ Hippocampal_tail * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.56035 -0.03390 0.04314 0.08288 0.16729

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 8.706e-01 2.281e-01 3.817 0.000265 ***

Hippocampal_tail 2.147e-05 1.933e-04 0.111 0.911854

GroupOlder Adults 1.699e-02 3.109e-01 0.055 0.956560

Hippocampal_tail:GroupOlder Adults -6.851e-05 2.735e-04 -0.250 0.802844

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.141 on 80 degrees of freedom

Multiple R-squared: 0.04513, Adjusted R-squared: 0.009327

F-statistic: 1.26 on 3 and 80 DF, p-value: 0.2936

Call:

lm(formula = acc_mean.learning ~ Hippocampal_tail + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.56378 -0.03264 0.04813 0.08091 0.16454

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 9.108e-01 1.612e-01 5.651 2.3e-07 ***

Hippocampal_tail -1.276e-05 1.359e-04 -0.094 0.9254

GroupOlder Adults -6.046e-02 3.286e-02 -1.840 0.0694 .

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.1402 on 81 degrees of freedom

Multiple R-squared: 0.04439, Adjusted R-squared: 0.02079

F-statistic: 1.881 on 2 and 81 DF, p-value: 0.159

Call:

lm(formula = rt_c_mean.learning ~ Hippocampal_tail * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-1524.6 -403.4 -85.8 311.4 3906.8

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1232.1159 1192.3848 1.033 0.305

Hippocampal_tail 0.4144 1.0105 0.410 0.683

GroupOlder Adults 1699.4404 1625.4811 1.045 0.299

Hippocampal_tail:GroupOlder Adults -0.8648 1.4296 -0.605 0.547

Residual standard error: 737.2 on 80 degrees of freedom

Multiple R-squared: 0.2043, Adjusted R-squared: 0.1744

F-statistic: 6.845 on 3 and 80 DF, p-value: 0.0003655

Call:

lm(formula = rt_c_mean.learning ~ Hippocampal_tail + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-1495.2 -415.6 -78.3 315.9 3867.1

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1739.50446 844.13529 2.061 0.0425 *

Hippocampal_tail -0.01769 0.71201 -0.025 0.9802

GroupOlder Adults 721.76536 172.08137 4.194 6.95e-05 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 734.3 on 81 degrees of freedom

Multiple R-squared: 0.2006, Adjusted R-squared: 0.1809

F-statistic: 10.16 on 2 and 81 DF, p-value: 0.0001152

Call:

lm(formula = acc_mean.test ~ Hippocampal_head * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.22040 -0.07173 0.01559 0.07299 0.15640

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1.142e+00 1.844e-01 6.192 2.41e-08 ***

Hippocampal_head -6.827e-05 5.315e-05 -1.284 0.2027

GroupOlder Adults -5.673e-01 2.502e-01 -2.268 0.0260 *

Hippocampal_head:GroupOlder Adults 1.541e-04 7.493e-05 2.057 0.0429 *

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.0952 on 80 degrees of freedom

Multiple R-squared: 0.1296, Adjusted R-squared: 0.09698

F-statistic: 3.971 on 3 and 80 DF, p-value: 0.01082

Call:

lm(formula = acc_mean.test ~ Hippocampal_head + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.24185 -0.06762 0.01380 0.06941 0.15168

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 8.738e-01 1.330e-01 6.569 4.52e-09 ***

Hippocampal_head 9.277e-06 3.820e-05 0.243 0.8088

GroupOlder Adults -5.492e-02 2.358e-02 -2.329 0.0224 *

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.09708 on 81 degrees of freedom

Multiple R-squared: 0.08358, Adjusted R-squared: 0.06096

F-statistic: 3.694 on 2 and 81 DF, p-value: 0.02916

Call:

lm(formula = rt_c_mean.test ~ Hippocampal_head * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-417.59 -137.50 -1.05 114.96 612.22

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 2250.14650 400.73076 5.615 2.75e-07 ***

Hippocampal_head 0.05575 0.11548 0.483 0.631

GroupOlder Adults 410.94354 543.58326 0.756 0.452

Hippocampal_head:GroupOlder Adults -0.02296 0.16281 -0.141 0.888

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 206.9 on 80 degrees of freedom

Multiple R-squared: 0.3907, Adjusted R-squared: 0.3679

F-statistic: 17.1 on 3 and 80 DF, p-value: 1.131e-08

Call:

lm(formula = rt_c_mean.test ~ Hippocampal_head + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-417.38 -139.36 -3.32 116.35 613.50

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 2.290e+03 2.817e+02 8.129 4.17e-12 ***

Hippocampal_head 4.420e-02 8.091e-02 0.546 0.586

GroupOlder Adults 3.346e+02 4.993e+01 6.701 2.53e-09 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 205.6 on 81 degrees of freedom

Multiple R-squared: 0.3906, Adjusted R-squared: 0.3755

F-statistic: 25.96 on 2 and 81 DF, p-value: 1.945e-09

Call:

lm(formula = acc_mean.test ~ Hippocampal_tail * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.23819 -0.05677 0.02205 0.06771 0.17914

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 8.767e-01 1.568e-01 5.591 3.03e-07 ***

Hippocampal_tail 2.483e-05 1.329e-04 0.187 0.852

GroupOlder Adults -1.893e-01 2.138e-01 -0.886 0.379

Hippocampal_tail:GroupOlder Adults 1.233e-04 1.880e-04 0.656 0.514

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.09695 on 80 degrees of freedom

Multiple R-squared: 0.09732, Adjusted R-squared: 0.06346

F-statistic: 2.875 on 3 and 80 DF, p-value: 0.04128

Call:

lm(formula = acc_mean.test ~ Hippocampal_tail + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.23559 -0.05522 0.01669 0.07115 0.16763

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 8.044e-01 1.111e-01 7.243 2.28e-10 ***

Hippocampal_tail 8.645e-05 9.367e-05 0.923 0.3588

GroupOlder Adults -4.986e-02 2.264e-02 -2.202 0.0305 *

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.09661 on 81 degrees of freedom

Multiple R-squared: 0.09246, Adjusted R-squared: 0.07005

F-statistic: 4.126 on 2 and 81 DF, p-value: 0.01966

Call:

lm(formula = rt_c_mean.test ~ Hippocampal_tail * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-420.20 -123.31 -14.39 112.82 611.27

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1897.2309 329.3795 5.760 1.5e-07 ***

Hippocampal_tail 0.4647 0.2791 1.665 0.0999 .

GroupOlder Adults 958.8544 449.0163 2.135 0.0358 *

Hippocampal_tail:GroupOlder Adults -0.5479 0.3949 -1.387 0.1692

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 203.7 on 80 degrees of freedom

Multiple R-squared: 0.4095, Adjusted R-squared: 0.3873

F-statistic: 18.49 on 3 and 80 DF, p-value: 3.32e-09

Call:

lm(formula = rt_c_mean.test ~ Hippocampal_tail + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-418.57 -138.53 -24.57 109.54 602.28

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 2218.7149 235.4315 9.424 1.15e-14 ***

Hippocampal_tail 0.1910 0.1986 0.962 0.339

GroupOlder Adults 339.3944 47.9939 7.072 4.90e-10 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 204.8 on 81 degrees of freedom

Multiple R-squared: 0.3952, Adjusted R-squared: 0.3803

F-statistic: 26.47 on 2 and 81 DF, p-value: 1.425e-09



Call:

lm(formula = Hippocampal_head ~ sleep_time_mean_sleep + Group,

data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-708.92 -138.10 0.67 181.29 570.04

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 3474.52100 167.08274 20.795 < 2e-16 ***

sleep_time_mean_sleep -0.04161 0.41703 -0.100 0.921

GroupOlder Adults -268.94030 62.08466 -4.332 4.21e-05 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 282.3 on 81 degrees of freedom

Multiple R-squared: 0.191, Adjusted R-squared: 0.171

F-statistic: 9.561 on 2 and 81 DF, p-value: 0.0001871

Call:

lm(formula = Hippocampal_tail ~ sleep_time_mean_sleep + Group,

data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-351.11 -55.08 11.93 72.01 270.93

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1116.0215 67.4855 16.537 < 2e-16 ***

sleep_time_mean_sleep 0.1510 0.1684 0.896 0.372812

GroupOlder Adults -89.9853 25.0763 -3.588 0.000568 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 114 on 81 degrees of freedom

Multiple R-squared: 0.1394, Adjusted R-squared: 0.1181

F-statistic: 6.558 on 2 and 81 DF, p-value: 0.002291

Call:

lm(formula = Hippocampal_tail ~ actphi * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-324.89 -49.89 0.72 67.34 286.91

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1222.202 204.501 5.976 6.44e-08 ***

actphi -3.339 12.481 -0.268 0.790

GroupOlder Adults -435.455 271.720 -1.603 0.113

actphi:GroupOlder Adults 23.961 17.480 1.371 0.174

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 112.9 on 78 degrees of freedom

(2 observations deleted due to missingness)

Multiple R-squared: 0.1463, Adjusted R-squared: 0.1135

F-statistic: 4.456 on 3 and 78 DF, p-value: 0.006083

Call:

lm(formula = Hippocampal_head ~ actphi + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-707.66 -147.58 -11.57 182.13 567.19

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 3579.604 363.290 9.853 2.12e-15 ***

actphi -7.699 22.081 -0.349 0.728281

GroupOlder Adults -278.751 74.213 -3.756 0.000329 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 285.2 on 79 degrees of freedom

(2 observations deleted due to missingness)

Multiple R-squared: 0.1834, Adjusted R-squared: 0.1628

F-statistic: 8.873 on 2 and 79 DF, p-value: 0.0003339

Call:

lm(formula = Hippocampal_tail ~ actphi + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-334.17 -53.61 0.11 64.75 278.50

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1022.836 144.563 7.075 5.36e-10 ***

actphi 8.878 8.787 1.010 0.3154

GroupOlder Adults -65.165 29.532 -2.207 0.0302 *

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 113.5 on 79 degrees of freedom

(2 observations deleted due to missingness)

Multiple R-squared: 0.1258, Adjusted R-squared: 0.1036

F-statistic: 5.682 on 2 and 79 DF, p-value: 0.004949

Call:

lm(formula = Hippocampal_head ~ IS + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-750.57 -143.71 -19.09 204.23 527.53

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 3347.92 128.07 26.141 < 2e-16 ***

IS 286.41 281.95 1.016 0.313

GroupOlder Adults -321.52 72.91 -4.410 3.55e-05 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 282.7 on 72 degrees of freedom

(9 observations deleted due to missingness)

Multiple R-squared: 0.2218, Adjusted R-squared: 0.2001

F-statistic: 10.26 on 2 and 72 DF, p-value: 0.0001202

Call:

lm(formula = Hippocampal_tail ~ IS + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-283.81 -66.85 12.38 88.11 239.18

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1075.86 52.78 20.385 < 2e-16 ***

IS 221.43 116.19 1.906 0.060673 .

GroupOlder Adults -106.15 30.05 -3.533 0.000722 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 116.5 on 72 degrees of freedom

(9 observations deleted due to missingness)

Multiple R-squared: 0.1493, Adjusted R-squared: 0.1256

F-statistic: 6.316 on 2 and 72 DF, p-value: 0.00297



Call:

lm(formula = cvlt_1 ~ sleep_time_mean_sleep + age, data = filter(dmem2,

Group == “Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-3.5170 -0.8654 0.2169 0.9648 2.3303

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 8.960868 2.965868 3.021 0.00437 **

sleep_time_mean_sleep 0.004266 0.002506 1.702 0.09650 .

age -0.063447 0.040510 -1.566 0.12518

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 1.407 on 40 degrees of freedom

(1 observation deleted due to missingness)

Multiple R-squared: 0.1209, Adjusted R-squared: 0.07698

F-statistic: 2.751 on 2 and 40 DF, p-value: 0.07593

Call:

lm(formula = cvlt_sdelay_recall ~ sleep_time_mean_sleep + age,

data = filter(dmem2, Group == “Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-6.5870 -2.0318 0.4958 2.0471 4.9189

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 15.331804 6.386172 2.401 0.0211 *

sleep_time_mean_sleep 0.010611 0.005396 1.966 0.0562 .

age -0.123029 0.087228 -1.410 0.1661

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 3.029 on 40 degrees of freedom

(1 observation deleted due to missingness)

Multiple R-squared: 0.1307, Adjusted R-squared: 0.08725

F-statistic: 3.007 on 2 and 40 DF, p-value: 0.06071

Call:

lm(formula = cvlt_ldelay_recall ~ sleep_time_mean_sleep + age,

data = filter(dmem2, Group == “Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-8.6033 -1.6688 0.4091 1.6829 4.7386

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 16.680939 6.106533 2.732 0.00933 **

sleep_time_mean_sleep 0.006696 0.005160 1.298 0.20186

age -0.115868 0.083408 -1.389 0.17247

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 2.896 on 40 degrees of freedom

(1 observation deleted due to missingness)

Multiple R-squared: 0.08502, Adjusted R-squared: 0.03927

F-statistic: 1.858 on 2 and 40 DF, p-value: 0.1691

Call:

lm(formula = cvlt_recognition_hits ~ sleep_time_mean_sleep +

age, data = filter(dmem2, Group == “Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-3.8920 -0.6978 0.1086 0.9122 1.6265

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 17.9055295 2.6833891 6.673 5.37e-08 ***

sleep_time_mean_sleep 0.0006457 0.0022675 0.285 0.777

age -0.0490041 0.0366521 -1.337 0.189

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 1.273 on 40 degrees of freedom

(1 observation deleted due to missingness)

Multiple R-squared: 0.04515, Adjusted R-squared: -0.002594

F-statistic: 0.9457 on 2 and 40 DF, p-value: 0.3969

Call:

lm(formula = cvlt_1 ~ IS, data = filter(dmem2, Group == “Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-3.1033 -1.3262 -0.2173 1.2568 2.8241

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 6.860 1.069 6.419 1.7e-07 ***

IS -1.037 1.954 -0.530 0.599

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 1.504 on 37 degrees of freedom

(5 observations deleted due to missingness)

Multiple R-squared: 0.007547, Adjusted R-squared: -0.01928

F-statistic: 0.2814 on 1 and 37 DF, p-value: 0.599

Call:

lm(formula = cvlt_sdelay_recall ~ IS, data = filter(dmem2, Group ==

“Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-5.7768 -1.7768 0.3344 2.5294 5.0016

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 14.168 2.260 6.270 2.71e-07 ***

IS -5.560 4.132 -1.346 0.187

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 3.18 on 37 degrees of freedom

(5 observations deleted due to missingness)

Multiple R-squared: 0.04666, Adjusted R-squared: 0.02089

F-statistic: 1.811 on 1 and 37 DF, p-value: 0.1866

Call:

lm(formula = cvlt_ldelay_recall ~ IS, data = filter(dmem2, Group ==

“Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-8.0911 -2.0285 -0.1671 2.0532 4.7568

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 13.411 2.105 6.371 1.98e-07 ***

IS -3.803 3.849 -0.988 0.33

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 2.962 on 37 degrees of freedom

(5 observations deleted due to missingness)

Multiple R-squared: 0.02571, Adjusted R-squared: -0.0006254

F-statistic: 0.9763 on 1 and 37 DF, p-value: 0.3295

Call:

lm(formula = cvlt_recognition_hits ~ IS, data = filter(dmem2,

Group == “Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-3.1625 -0.8340 0.3796 1.0134 1.7459

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 16.4211 0.8962 18.323 <2e-16 ***

IS -3.0521 1.6388 -1.862 0.0705 .

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 1.261 on 37 degrees of freedom

(5 observations deleted due to missingness)

Multiple R-squared: 0.08571, Adjusted R-squared: 0.061

F-statistic: 3.469 on 1 and 37 DF, p-value: 0.07049

Call:

lm(formula = cvlt_1 ~ actphi, data = filter(dmem2, Group == “Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-3.3592 -1.3124 -0.3293 1.5824 2.6479

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 6.89590 2.36091 2.921 0.00565 **

actphi -0.03594 0.16126 -0.223 0.82473

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 1.481 on 41 degrees of freedom

(1 observation deleted due to missingness)

Multiple R-squared: 0.00121, Adjusted R-squared: -0.02315

F-statistic: 0.04968 on 1 and 41 DF, p-value: 0.8247

Call:

lm(formula = cvlt_sdelay_recall ~ actphi, data = filter(dmem2,

Group == “Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-6.1032 -1.9656 0.5189 2.1995 5.0930

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 8.4578 5.0963 1.660 0.105

actphi 0.1920 0.3481 0.552 0.584

Residual standard error: 3.197 on 41 degrees of freedom

(1 observation deleted due to missingness)

Multiple R-squared: 0.007365, Adjusted R-squared: -0.01685

F-statistic: 0.3042 on 1 and 41 DF, p-value: 0.5842

Call:

lm(formula = cvlt_ldelay_recall ~ actphi, data = filter(dmem2,

Group == “Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-8.3577 -1.9687 0.2576 2.1735 4.8401

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 8.6903 4.7469 1.831 0.0744 .

actphi 0.1936 0.3242 0.597 0.5537

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 2.978 on 41 degrees of freedom

(1 observation deleted due to missingness)

Multiple R-squared: 0.008621, Adjusted R-squared: -0.01556

F-statistic: 0.3565 on 1 and 41 DF, p-value: 0.5537

Call:

lm(formula = cvlt_recognition_hits ~ actphi, data = filter(dmem2,

Group == “Older Adults”))

Residuals:

Min 1Q Median 3Q Max

-3.8003 -0.8419 0.1619 1.0950 1.3514

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 13.84854 2.04489 6.772 3.46e-08 ***

actphi 0.06784 0.13967 0.486 0.63

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 1.283 on 41 degrees of freedom

(1 observation deleted due to missingness)

Multiple R-squared: 0.005721, Adjusted R-squared: -0.01853

F-statistic: 0.2359 on 1 and 41 DF, p-value: 0.6298

Welch Two Sample t-test

data: acc_mean.test by sleepundersix

t = 0.48569, df = 12.093, p-value = 0.6359

alternative hypothesis: true difference in means is not equal to 0

95 percent confidence interval:

-0.06941689 0.10928618

sample estimates:

mean in group Under 6 h mean in group At least 6 h

0.8638889 0.8439542

Welch Two Sample t-test

data: rt_c_mean.test by sleepundersix

t = -3.4084, df = 24.196, p-value = 0.002291

alternative hypothesis: true difference in means is not equal to 0

95 percent confidence interval:

-317.24291 -78.00989

sample estimates:

mean in group Under 6 h mean in group At least 6 h

2612.949 2810.576

Welch Two Sample t-test

data: cvlt_ldelay_recall by sleepundersix

t = 0.2167, df = 13.895, p-value = 0.8316

alternative hypothesis: true difference in means is not equal to 0

95 percent confidence interval:

-2.185640 2.676549

sample estimates:

mean in group Under 6 h mean in group At least 6 h

11.70000 11.45455

Welch Two Sample t-test

data: cvlt_recognition_hits by sleepundersix

t = 1.2639, df = 22.027, p-value = 0.2195

alternative hypothesis: true difference in means is not equal to 0

95 percent confidence interval:

-0.3028723 1.2483268

sample estimates:

mean in group Under 6 h mean in group At least 6 h

15.20000 14.72727

Call:

lm(formula = acc_mean.learning ~ sleep_time_mean_sleep * Group,

data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.56251 -0.03620 0.02417 0.10247 0.16240

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 8.956e-01 1.431e-01 6.256 1.83e-08

sleep_time_mean_sleep 6.723e-07 3.664e-04 0.002 0.999

GroupOlder Adults -2.342e-01 1.755e-01 -1.335 0.186

sleep_time_mean_sleep:GroupOlder Adults 4.338e-04 4.416e-04 0.983 0.329

(Intercept) ***

sleep_time_mean_sleep

GroupOlder Adults

sleep_time_mean_sleep:GroupOlder Adults

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.1384 on 80 degrees of freedom

Multiple R-squared: 0.08004, Adjusted R-squared: 0.04554

F-statistic: 2.32 on 3 and 80 DF, p-value: 0.08155

Call:

lm(formula = acc_mean.learning ~ sleep_time_mean_sleep + Group,

data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.56547 -0.03944 0.02679 0.09408 0.16274

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 0.7802345 0.0819040 9.526 7.26e-15 ***

sleep_time_mean_sleep 0.0002994 0.0002044 1.465 0.1469

GroupOlder Adults -0.0644313 0.0304339 -2.117 0.0373 *

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.1384 on 81 degrees of freedom

Multiple R-squared: 0.06894, Adjusted R-squared: 0.04595

F-statistic: 2.999 on 2 and 81 DF, p-value: 0.05541

Call:

lm(formula = rt_c_mean.learning ~ sleep_time_mean_sleep * Group,

data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-1343.2 -439.7 -102.1 358.2 3854.8

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 2216.583 761.014 2.913 0.00464 **

sleep_time_mean_sleep -1.289 1.948 -0.662 0.50988

GroupOlder Adults -20.670 932.877 -0.022 0.98238

sleep_time_mean_sleep:GroupOlder Adults 1.900 2.347 0.809 0.42066

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 735.9 on 80 degrees of freedom

Multiple R-squared: 0.2071, Adjusted R-squared: 0.1774

F-statistic: 6.965 on 3 and 80 DF, p-value: 0.0003186

Call:

lm(formula = rt_c_mean.learning ~ sleep_time_mean_sleep + Group,

data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-1489.3 -417.7 -78.6 317.9 3865.1

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1.711e+03 4.346e+02 3.938 0.000173 ***

sleep_time_mean_sleep 1.889e-02 1.085e+00 0.017 0.986150

GroupOlder Adults 7.230e+02 1.615e+02 4.477 2.45e-05 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 734.3 on 81 degrees of freedom

Multiple R-squared: 0.2006, Adjusted R-squared: 0.1809

F-statistic: 10.16 on 2 and 81 DF, p-value: 0.0001153

Call:

lm(formula = acc_mean.test ~ sleep_time_mean_sleep * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.24417 -0.06875 0.01920 0.06881 0.16655

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 8.698e-01 1.007e-01 8.636 4.56e-13

sleep_time_mean_sleep 9.357e-05 2.578e-04 0.363 0.718

GroupOlder Adults -6.631e-02 1.235e-01 -0.537 0.593

sleep_time_mean_sleep:GroupOlder Adults 1.811e-05 3.107e-04 0.058 0.954

(Intercept) ***

sleep_time_mean_sleep

GroupOlder Adults

sleep_time_mean_sleep:GroupOlder Adults

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.09739 on 80 degrees of freedom

Multiple R-squared: 0.08914, Adjusted R-squared: 0.05498

F-statistic: 2.61 on 3 and 80 DF, p-value: 0.05716

Call:

lm(formula = acc_mean.test ~ sleep_time_mean_sleep + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.24483 -0.06885 0.01957 0.06902 0.16579

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 0.864961 0.057281 15.100 < 2e-16 ***

sleep_time_mean_sleep 0.000106 0.000143 0.742 0.46040

GroupOlder Adults -0.059220 0.021285 -2.782 0.00671 **

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.09679 on 81 degrees of freedom

Multiple R-squared: 0.0891, Adjusted R-squared: 0.06661

F-statistic: 3.962 on 2 and 81 DF, p-value: 0.02283

Call:

lm(formula = rt_c_mean.test ~ sleep_time_mean_sleep * Group,

data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-465.21 -132.18 -2.53 114.82 620.87

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 2.442e+03 2.110e+02 11.572 <2e-16

sleep_time_mean_sleep 3.004e-03 5.401e-01 0.006 0.996

GroupOlder Adults 9.044e+01 2.587e+02 0.350 0.728

sleep_time_mean_sleep:GroupOlder Adults 5.761e-01 6.509e-01 0.885 0.379

(Intercept) ***

sleep_time_mean_sleep

GroupOlder Adults

sleep_time_mean_sleep:GroupOlder Adults

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 204 on 80 degrees of freedom

Multiple R-squared: 0.4072, Adjusted R-squared: 0.385

F-statistic: 18.32 on 3 and 80 DF, p-value: 3.862e-09

Call:

lm(formula = rt_c_mean.test ~ sleep_time_mean_sleep + Group,

data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-450.65 -135.17 -11.76 109.99 617.05

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 2288.6427 120.5927 18.978 < 2e-16 ***

sleep_time_mean_sleep 0.3997 0.3010 1.328 0.188

GroupOlder Adults 315.9086 44.8099 7.050 5.4e-10 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 203.8 on 81 degrees of freedom

Multiple R-squared: 0.4014, Adjusted R-squared: 0.3866

F-statistic: 27.16 on 2 and 81 DF, p-value: 9.435e-10

Call:

lm(formula = acc_mean.learning ~ actphi * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.55244 -0.02597 0.03725 0.08182 0.18319

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1.123419 0.255790 4.392 3.49e-05 ***

actphi -0.014193 0.015612 -0.909 0.366

GroupOlder Adults -0.135316 0.339867 -0.398 0.692

actphi:GroupOlder Adults 0.003776 0.021864 0.173 0.863

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.1412 on 78 degrees of freedom

(2 observations deleted due to missingness)

Multiple R-squared: 0.05364, Adjusted R-squared: 0.01724

F-statistic: 1.474 on 3 and 78 DF, p-value: 0.2282

Call:

lm(formula = acc_mean.learning ~ actphi + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.55326 -0.02568 0.03703 0.08378 0.18669

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1.09201 0.17871 6.110 3.53e-08 ***

actphi -0.01227 0.01086 -1.129 0.2622

GroupOlder Adults -0.07697 0.03651 -2.108 0.0382 *

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.1403 on 79 degrees of freedom

(2 observations deleted due to missingness)

Multiple R-squared: 0.05328, Adjusted R-squared: 0.02931

F-statistic: 2.223 on 2 and 79 DF, p-value: 0.115

Call:

lm(formula = rt_c_mean.learning ~ actphi * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-1365.3 -418.3 -72.4 293.4 3633.9

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 2659.28 1321.72 2.012 0.0477 *

actphi -57.71 80.67 -0.715 0.4765

GroupOlder Adults 1850.66 1756.16 1.054 0.2952

actphi:GroupOlder Adults -84.38 112.97 -0.747 0.4574

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 729.5 on 78 degrees of freedom

(2 observations deleted due to missingness)

Multiple R-squared: 0.2342, Adjusted R-squared: 0.2047

F-statistic: 7.95 on 3 and 78 DF, p-value: 0.0001084

Call:

lm(formula = rt_c_mean.learning ~ actphi + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-1402.7 -450.9 -65.5 313.7 3701.3

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 3361.34 926.57 3.628 0.000505 ***

actphi -100.73 56.32 -1.789 0.077516 .

GroupOlder Adults 546.71 189.28 2.888 0.004995 **

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 727.4 on 79 degrees of freedom

(2 observations deleted due to missingness)

Multiple R-squared: 0.2287, Adjusted R-squared: 0.2092

F-statistic: 11.71 on 2 and 79 DF, p-value: 3.512e-05

Call:

lm(formula = acc_mean.test ~ actphi * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.23996 -0.07085 0.02202 0.07274 0.15329

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 0.965842 0.179133 5.392 7.22e-07 ***

actphi -0.003663 0.010933 -0.335 0.738

GroupOlder Adults -0.102040 0.238013 -0.429 0.669

actphi:GroupOlder Adults 0.002611 0.015311 0.170 0.865

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.09887 on 78 degrees of freedom

(2 observations deleted due to missingness)

Multiple R-squared: 0.08277, Adjusted R-squared: 0.04749

F-statistic: 2.346 on 3 and 78 DF, p-value: 0.07919

Call:

lm(formula = acc_mean.test ~ actphi + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.23975 -0.07103 0.02459 0.07072 0.15546

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 0.944122 0.125155 7.544 6.71e-11 ***

actphi -0.002332 0.007607 -0.307 0.7600

GroupOlder Adults -0.061697 0.025567 -2.413 0.0181 *

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.09826 on 79 degrees of freedom

(2 observations deleted due to missingness)

Multiple R-squared: 0.08243, Adjusted R-squared: 0.0592

F-statistic: 3.548 on 2 and 79 DF, p-value: 0.03344

Call:

lm(formula = rt_c_mean.test ~ actphi * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-447.6 -116.6 -4.7 120.1 693.5

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 2764.36 368.07 7.510 8.3e-11 ***

actphi -19.85 22.46 -0.883 0.380

GroupOlder Adults 618.13 489.05 1.264 0.210

actphi:GroupOlder Adults -22.54 31.46 -0.716 0.476

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 203.1 on 78 degrees of freedom

(2 observations deleted due to missingness)

Multiple R-squared: 0.421, Adjusted R-squared: 0.3988

F-statistic: 18.91 on 3 and 78 DF, p-value: 2.599e-09

Call:

lm(formula = rt_c_mean.test ~ actphi + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-439.95 -124.73 -4.16 112.14 671.33

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 2951.87 257.96 11.443 < 2e-16 ***

actphi -31.34 15.68 -1.999 0.0491 *

GroupOlder Adults 269.86 52.70 5.121 2.09e-06 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 202.5 on 79 degrees of freedom

(2 observations deleted due to missingness)

Multiple R-squared: 0.4172, Adjusted R-squared: 0.4025

F-statistic: 28.28 on 2 and 79 DF, p-value: 5.459e-10

Call:

lm(formula = acc_mean.learning ~ IS * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.57683 -0.02783 0.03023 0.07388 0.16918

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 0.95005 0.09261 10.258 1.17e-15 ***

IS -0.08864 0.21298 -0.416 0.679

GroupOlder Adults -0.11517 0.13304 -0.866 0.390

IS:GroupOlder Adults 0.08316 0.27493 0.302 0.763

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.135 on 71 degrees of freedom

(9 observations deleted due to missingness)

Multiple R-squared: 0.08798, Adjusted R-squared: 0.04944

F-statistic: 2.283 on 3 and 71 DF, p-value: 0.08641

Call:

lm(formula = acc_mean.learning ~ IS + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.57826 -0.03125 0.03401 0.08086 0.17598

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 0.92902 0.06079 15.283 <2e-16 ***

IS -0.03873 0.13383 -0.289 0.7731

GroupOlder Adults -0.07634 0.03461 -2.206 0.0306 *

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.1342 on 72 degrees of freedom

(9 observations deleted due to missingness)

Multiple R-squared: 0.0868, Adjusted R-squared: 0.06144

F-statistic: 3.422 on 2 and 72 DF, p-value: 0.03804

Call:

lm(formula = rt_c_mean.learning ~ IS * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-1553.7 -434.2 -67.1 297.9 3779.5

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1668.26 521.65 3.198 0.00207 **

IS 95.32 1199.62 0.079 0.93689

GroupOlder Adults 1289.10 749.36 1.720 0.08974 .

IS:GroupOlder Adults -971.49 1548.52 -0.627 0.53243

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 760.6 on 71 degrees of freedom

(9 observations deleted due to missingness)

Multiple R-squared: 0.2234, Adjusted R-squared: 0.1906

F-statistic: 6.808 on 3 and 71 DF, p-value: 0.0004248

Call:

lm(formula = rt_c_mean.learning ~ IS + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-1547.7 -412.6 -62.1 317.0 3797.1

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 1914.0 343.1 5.578 4.01e-07 ***

IS -487.7 755.4 -0.646 0.521

GroupOlder Adults 835.4 195.3 4.276 5.74e-05 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 757.4 on 72 degrees of freedom

(9 observations deleted due to missingness)

Multiple R-squared: 0.2191, Adjusted R-squared: 0.1974

F-statistic: 10.1 on 2 and 72 DF, p-value: 0.000136

Call:

lm(formula = acc_mean.test ~ IS * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.24823 -0.06037 0.02654 0.06488 0.17941

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 0.92182 0.06631 13.901 <2e-16 ***

IS -0.01505 0.15250 -0.099 0.922

GroupOlder Adults -0.12550 0.09526 -1.317 0.192

IS:GroupOlder Adults 0.10492 0.19686 0.533 0.596

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.0967 on 71 degrees of freedom

(9 observations deleted due to missingness)

Multiple R-squared: 0.1299, Adjusted R-squared: 0.09318

F-statistic: 3.535 on 3 and 71 DF, p-value: 0.01898

Call:

lm(formula = acc_mean.test ~ IS + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-0.25066 -0.05939 0.02616 0.06746 0.16828

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 0.89529 0.04359 20.541 < 2e-16 ***

IS 0.04791 0.09595 0.499 0.61908

GroupOlder Adults -0.07650 0.02481 -3.083 0.00291 **

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 0.09621 on 72 degrees of freedom

(9 observations deleted due to missingness)

Multiple R-squared: 0.1265, Adjusted R-squared: 0.1022

F-statistic: 5.212 on 2 and 72 DF, p-value: 0.007694

Call:

lm(formula = rt_c_mean.test ~ IS * Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-426.24 -123.89 -24.89 121.07 597.08

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 2447.85 146.51 16.707 <2e-16 ***

IS -52.79 336.94 -0.157 0.876

GroupOlder Adults 228.60 210.47 1.086 0.281

IS:GroupOlder Adults 223.42 434.93 0.514 0.609

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 213.6 on 71 degrees of freedom

(9 observations deleted due to missingness)

Multiple R-squared: 0.4049, Adjusted R-squared: 0.3798

F-statistic: 16.1 on 3 and 71 DF, p-value: 4.387e-08

Call:

lm(formula = rt_c_mean.test ~ IS + Group, data = dmem2)

Residuals:

Min 1Q Median 3Q Max

-423.15 -123.04 -14.88 128.27 601.95

Coefficients:

Estimate Std. Error t value Pr(>|t|)

(Intercept) 2391.34 96.28 24.836 < 2e-16 ***

IS 81.29 211.97 0.383 0.702

GroupOlder Adults 332.95 54.82 6.074 5.34e-08 ***

Signif. codes: 0 ‘’ 0.001 ’’ 0.01 ’’ 0.05 ‘.’ 0.1 ’ ’ 1

Residual standard error: 212.5 on 72 degrees of freedom

(9 observations deleted due to missingness)

Multiple R-squared: 0.4027, Adjusted R-squared: 0.3861

F-statistic: 24.27 on 2 and 72 DF, p-value: 8.774e-09

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